Bespoke schemes: practical guidance: When to draw up a new scheme
One of the objectives of bespoke scheme agreements is to bring all the agreed aspects of a scheme together rather than have them scattered across the correspondence of many years. When existing schemes are changed, you need to judge whether the record of correspondence on the issue is a sufficient record of the change, or whether the change should be recorded by the issue of a new agreement.
Clearly, the greater the number of changes recorded in separate correspondence, the greater the opportunity for disagreement about what has been agreed. The number of changes needed before a new agreement is required will vary depending on the complexity of the business and the availability of resource.